a) Field of the Invention
The present invention relates to a cutting device for use to separate the pulp from the skin of fruits and more especially of citrus fruits such as grapefruits, limes, lemons, cumquats, tangerines, oranges and the like eventhough the same device could also be used with other fruits such as melons, kiwis, apples and the like.
b) Brief Description of the Prior Art
As is known, citrus fruits are spherical in shape and have an inner part made of an edible pulp and an outer part called  less than  less than rind greater than  greater than , which consists of a semi-rigid skin. When the fruit is cut in half, its pulp defines a plurality of sector shaped segments each consisting of an edible soft part called  less than  less than lith greater than  greater than , which is surrounded by two opposite semi-rigid fiber partitions. The fiber partitions extend radially from a central fibrous portion up to the rind. Seeds or  less than  less than pips greater than  greater than  are often lodged into the lith.
Special knives are provided for cutting the edible part of the pulp from citrus fruits. These knives have a blade that is curved to follow the contour of the skin and they need some manual dexterity to derind the pulp, i.e. scrape the pulp about its interface with the skin.
Other tools also exist, which consist of a semi-spherical open knife made of radially extending blades which can be pressed onto a half-fruit held into a cup, in order to slice its pulp and separate it from the skin while the juice is being collected into an adjacent container. In this connection, reference can be made to U.S. Pat. No. 1,040,582 granted in 1912 and U.S. Pat. No. 1,423,490 granted in 1922.
U.S. Pat. No. 4,959,903 granted on Oct. 2, 1990 discloses a cutting device which is presently sold worldwide under the trademark STARFRIT/CITRUS EXPRESS and which comprises:
an upwardly opened container for receiving pulp segments of the fruit;
a fruit derinding member sized and shaped to fit on top of the container;
a fruit segmenting member sized and shaped to fit above the fruit derinding member on top of the container; and
an inverted cup-shaped cover sized and shaped to cover the half-section of the fruit.
The fruit segmenting member comprises a ring which is freely mounted on top of the fruit derinding member in use. It also comprises a set of arcuate knives upwardly projecting from the ring. The knives are spaced apart and converge towards a common apex where they are connected to each other.
The fruit derinding member comprises another ring and at least one arcuate blade upwardly projecting from the other ring. This arcuate blade has a peripherally projecting edge and is shaped, sized and connected onto the other ring in such a manner to extend contiguously to any one of the arcuate knives of the fruit segmenting member when the fruit segment member is fitted on top of the base with the fruit derinding member in between.
In use, the flat face of the half-fruit is applied directly onto the fruit-segmenting member and manually pressed down with the cup-shaped cover in order to segment radially the fruit into a plurality of pulp segments. Then, the cover, the fruit and the fruit segmenting member are manually turned in unison on top of the fruit derinding member and the container, whereby the blade(s) of the fruit derinding member peels the pulp segment out from the skin. After having been cut, the so-peeled segments fall into the container where they can be recovered.
The object of the present invention is to provide a cutting device for derinding a half-section of a fruit, which device is simple in structure, easy to handle and to use and very efficient to achieve the requested derinding.
More specifically, the invention provides a cutting device for derinding a half-section of a fruit, especially but not exclusively a citrus fruit, which comprises:
an upwardly opened container having a vertical axis and an annular upper edge concentric with the vertical axis;
an upwardly opened cup for receiving and holding the half-section to be derinded, the cup being coaxially mounted in a removable manner within the container at a short distance from the upper edge thereof, and having a central portion with a bottom;
a knife-supporting element removably mounted in a rotatable manner coaxially on top of the container, the element having an annular bottom edge shaped and sized to fit and be slidable onto the upper edge of the container, the element also having a knife receiving sleeve that extends at a radial distance from the vertical axis and projects downwardly towards the bottom of the central portion of the cup; and
a knife having a blade removably insertable into the sleeve after the half-section has been positioned in the cup and the knife-supporting element has been positioned on top of the container.
Once inserted into the sleeve, the blade of the knife penetrates into the fruit at a short distance from the rind thereof and allows the half-section of said fruit to be derinded upon rotation of the knife supporting element with respect to the container.
In accordance with a particularly preferred embodiment of the invention, the device comprises two or more cups having central portions of different sizes to receive fruits of corresponding different sizes. Then, the knife-supporting element comprises a corresponding number knife receiving sleeves located at different radial distances to allow optimum adjustment of the position of the blade of the knife depending on the size of the central portion of the selected cup.
The invention, its structure, its operation and its advantages will be better understood upon reading the following non-restrictive description of preferred embodiments thereof, made with reference to the accompanying drawings.